Multiple imaging modality light source

ABSTRACT

A method for generating light from a medical light source includes emitting light in a visible wavelength spectrum from a first light of the medical light source, emitting light in a first infrared spectrum from a first light emitter of a second light, redirecting light emitted from the first light emitter by at least one optical element of the second light, emitting light in a second infrared spectrum from a second light emitter of the second light, and redirecting the light emitted from the second light emitter by the at least one optical element of the second light.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.15/458,137, filed Mar. 14, 2017, which claims the benefit of U.S.Provisional Application No. 62/321,414, filed Apr. 12, 2016, the entirecontents of each of which are incorporated by reference herein.

BACKGROUND OF THE INVENTION

The present invention relates generally to a solid state system forproviding illumination from an external light source through aninstrument to an object, such as a patient surgical site. The externallight source includes components for providing light in the visiblespectrum as well as light in the ultraviolet and/or infrared spectrums.

Endoscopic systems are used to inspect regions within a body duringsurgery. Endoscopic systems typically include an endoscope, a lightsource, and an imaging device such as a camera head. Typically, anendoscope includes a rigid or flexible elongated insertion tube equippedwith a set of optical fibers that extend from a proximal handle throughthe endoscope body to a distal viewing tip. An external light sourceprovides light to the optic fibers via a cable that attaches to a postor other structure on the endoscope. The endoscope also receives imagesand transmits them to the imaging device for providing an image to amonitor or other display apparatus for viewing by a surgeon.

In one commercial embodiment, an endoscopic system includes a solidstate light source that generates white light which is conveyed to adistal end of the endoscope via a light guide. The light guide includesmultiple fibers and is connected between an output connector of thelight source and a light post of the endoscope. The white lightilluminates a working area at the distal end of the endoscope. Thecamera, connected to a handle of the endoscope, generates video signalsrepresentative of images at the working area for display on a videomonitor.

The light source includes an optical system and a lens array used tocollimate light from an LED array. A focusing lens focuses the lightonto the light guide. The lenses collect light emitted by LEDs. Thelenses may be single lenses, such as single or double aspherics,compound lenses, radiant index type lenses, or combinations of each ofthese. Other arrangements have lens arrays that are implemented as partof an LED array by adhesion, fusion, or other means. Some arrangementshave a rectangular-shaped LED and lens array.

The focal length of the lens and the diameter of the lens are chosen onthe order of a few millimeters. The actual values are selected based onthe size of the LED emitting surface which determines the field of viewof the lens.

The collected light from the lens array travels to a focusing lens. Thefocusing lens projects the light image of each LED emitting surface ontoan entrance face of the light guide. The image is magnified so that thesize is approximately equal to the size of the entrance face of thelight guide. The light guide transports the light to the endoscope. Thelight passes through the endoscope to illuminate a surgical site. Lightis reflected off of the surgical site which is received by the endoscopeand transmitted to the camera head. The camera head provides images ofthe surgical site for display on the monitor.

Another endoscopic system that has been designed is described incommonly-owned PCT Application No. WO 2010/059197 A2.

The above-described endoscopic systems do not concern themselves withthe ability of providing specific wavelengths of light or excitation offluorescent markers in an object, such as a body part at a surgicalsite. While there are systems on the market that do provide excitationlight for fluorescent markers, these systems typically use incandescentlight and/or multiple light sources and multiple components to transmitlight to the surgical site, and multiple components to separate thelight emitted.

SUMMARY OF THE INVENTION

One embodiment of the present invention includes a single light sourcewhich is capable of providing white light, and providing ultravioletlight. The embodiment includes one or more movable light filters toprovide a variety of illumination modes.

Another embodiment of the invention employs a light source to providelight in the red, blue, green, ultraviolet and infrared wavelengthspectra to an endoscope which transports the light to a surgical site.Reflected light and fluorescent light from fluorescent markers at thesurgical site are then transmitted through the endoscope, through anotch filter, for separation of light in the desired spectra, then tothe imaging device.

Yet another embodiment of the invention includes two or more infraredlaser diodes in the same light engine slot. The two or more infraredlaser diodes are each connected to the same heat sink.

Still another embodiment of the invention employs a modular light enginewhich may be replaced with other modular light engines and/or mayprovide additional illumination modes to an existing light source.

Other advantages, objects and/or purposes of the invention will beapparent to persons familiar with constructions of this general typeupon reading the following specification and inspecting the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an illustration of an endoscopic camera arrangement which isan embodiment of the present invention.

FIG. 2 is a diagram of a portion of the endoscopic camera arrangement ofFIG. 1 and an object with fluorescent markers in it.

FIG. 3A is an enlarged, longitudinal and fragmentary cross-sectionalview of the distal end of a preferred endoscope.

FIG. 3B is an enlarged end view of the distal end of the endoscope asseen generally along line IIIB-IIIB in FIG. 3A.

FIG. 4 is a block diagram of a light source of the endoscopic system ofFIG. 1.

FIG. 5 is a diagrammatic view of the light and filter portion of thelight source of FIG. 4 with movable filters out of the light paths, andshowing a light emission first mode.

FIG. 6 is a diagrammatic view of the LED and filter portion of FIG. 5with movable filters in the light paths of an ultraviolet light and agreen light, and showing a light emission second mode.

FIG. 7 is a diagrammatic view of the LED and filter portion of FIG. 5,and showing a light emission third mode.

FIG. 8 is a diagrammatic view of the LED and filter portion of FIG. 5,and showing a light emission fourth mode.

FIG. 9 is a diagrammatic view of the LED and filter portion of FIG. 5,and showing a light emission fifth mode.

FIG. 10 is a diagrammatic view of a second embodiment of the light andfilter portion of the light source of the endoscopic system of FIG. 1,and having LEDs for ultraviolet light, blue light, green light, and redlight, and a laser diode for infrared light.

FIG. 11 is a diagrammatic view of a third embodiment of the light andfilter portion of the light source of the endoscopic system of FIG. 1,and having LEDs for blue light, green light, and red light, multiplelaser diodes for infrared light, and optionally an LED for ultravioletlight.

FIG. 12 is a perspective view of a single light source slot in a lightengine having two infrared laser diodes, both connected to a single heatsink.

FIG. 13A is a perspective view of a light source stack which includes aplurality of laser diodes.

FIG. 13B is an elevational side view of the light source stack,including infrared laser diodes, and a heat sink, of FIG. 12.

FIG. 14 is a diagrammatic view of a fourth embodiment of the light andfilter portion of the light source of the endoscopic system of FIG. 1,and having LEDs for white light and UV light and multiple laser diodesfor infrared light.

FIG. 15 is a perspective view of a light source with a modular lightengine.

FIG. 16 is a rear perspective view of the light source with modularlight engine of FIG. 15, with the housing of the light source removed.

FIG. 17 is a perspective view of the modular light engine of FIG. 15with the housing removed.

FIG. 18 is a perspective view of a light source with a modular upgradeto the light engine.

FIG. 19 is a perspective view of the modular upgrade of FIG. 18 with aportion of the housing removed.

FIG. 20 is an elevational view of the modular upgrade of FIG. 18 with aportion of the housing removed, and showing the light paths therein.

FIG. 21 is a top perspective view of a light module receiving base of alight source.

FIG. 22 is a perspective view of a portion of the light module receivingbase of FIG. 21.

FIG. 23 is a top plan view of an embodiment of a light module.

FIG. 24 is a top perspective view of the light module of FIG. 23.

FIG. 25 is a top perspective view of the light module of FIG. 23engaging with the base of FIG. 21.

FIG. 26 is a partially exploded view of an embodiment of a light moduleand a movable filter.

DETAILED DESCRIPTION

Certain terminology will be used in the following description forconvenience and reference only, and will not be limiting. For example,the words “upwardly, “downwardly,” “rightwardly,” and “leftwardly” willrefer to directions in the drawings to which reference is made. Thewords “inwardly”and “outwardly” will refer to directions toward and awayfrom, respectively, the geometric center of the arrangement, anddesignated parts thereof. This terminology includes the wordsspecifically mentioned, derivatives thereof, and words of similarimport.

FIG. 1 shows an endoscopic camera arrangement 10, including a scopeassembly 11 which may be utilized in endoscopic procedures. The scopeassembly 11 incorporates an endoscope or scope 12 which is coupled to acamera head 16 by a coupler 13 located at the distal end of the camerahead 16. Light is provided to the scope by a light source 14 via a lightguide 26, such as a fiber optic cable. The camera head 16 is coupled toa camera control unit (CCU) 18 by an electrical cable 15. The CCU 18 ispreferably connected to, and communicates with, the light source 14.Operation of the camera 16 is controlled, in part, by the CCU 18. Thecable 15 conveys video image data from the camera head 16 to the CCU 18and conveys various control signals bi-directionally between the camerahead 16 and the CCU 18. In one embodiment, the image data output by thecamera head 16 is digital.

A control or switch arrangement 17 is provided on the camera head 16 andallows a user to manually control various functions of the arrangement10. Voice commands are input into a microphone 25 mounted on a headset27 worn by the surgeon and coupled to a voice-control unit 23. Ahand-held control device 21, such as a tablet with a touch screen userinterface or a PDA, may be coupled to the voice control unit 23 as afurther control interface. In the illustrated embodiment, a recorder 31and a printer 33 are also coupled to the CCU 18. Additional devices,such as an image capture and archiving device, may be included in thearrangement 10 and coupled to the CCU 18. Video image data acquired bythe camera head 16 and processed by the CCU 18 is converted to images,which can be displayed on a monitor 20, recorded by the recorder 31,and/or used to generate static images, hard copies of which can beproduced by the printer 33.

FIG. 2 shows an embodiment of part of the endoscopic system 10 used toilluminate and receive light from an object 1, such as a surgical siteof a patient. The object 1, depending on the procedure, may includefluorescent or other imaging markers 2 therein. The markers 2 arepreferably comprised of indocyanine green (ICG) which is an FDA-approvedfluorescent dye for bile duct identification and sentinel lymph node(SLN) identification; a hexaminolevulinate hydrochloride imaging agentfor locating cancerous tissues such as tumors, also known as UVfluorescent imaging or more specifically, 5-ALA imaging; or afluorophore such as fluorescein, which is an FDA-approved fluorescentdye for cerebrospinal fluid identification.

FIGS. 3A and 3B illustrate the structure of a preferred embodiment ofthe endoscope 12 in greater detail at the distal end 38 thereof. A shaft36 of the endoscope 12 is defined by a substantially cylindrical andtubular outer housing 40 and an inner tubular housing 42 located withinthe outer housing 40. The outer and inner housings 40, 42 are sized suchthat an annular space 44 is defined therebetween which extends along asubstantial portion of the longitudinal extent of the shaft 36. Acylindrical optical fiber 46 is located within the annular space 44 andextends from the distal end 38 rearwardly to the proximal end of theendoscope 12 to receive electromagnetic radiation transmitted into theendoscope 12 via the light guide 26.

In the illustrated example, the inner tubular housing 42 encloses theinnermost functional components of the endoscope 12, such as an opticaltrain 48. The optical train 48 can comprise an image lens 50 at thedistal end 38 suitably fixed or connected to the inner surface of theinner tubular housing 42 with a corresponding generally annular imagelens casing 52. A distal window 54 is located at the distal terminus ofthe tubular outer housing 40, the inner tubular housing 42 and theoptical fiber 46. In one embodiment, the otherwise empty spaces in theoptical train 48, for instance the space between the image lens 50 andthe distal window 54, are hermetically sealed against the exterior ofthe endoscope 12 and filled with a specified fluid such as low-humiditynitrogen gas. Alternatively, one or more such spaces may be hermeticallysealed with respect to the exterior of the endoscope 12 andsubstantially devoid of fluid. The components and workings of theendoscopic system as described above are conventional and furtherdescription is accordingly not provided herein.

The illustrated endoscope 12 includes the distal window 54 on the distalend 38 thereof. The distal window 54 allows the imaging light comingfrom the optical fiber 46 to pass therethrough for illuminating thesurgical field. After passing through the distal window 54, the imaginglight reflects off of matter in the surgical field, for example, object1, and reflects back through and into the endoscope 12 through a centerarea of the distal window 54 to be passed to an eyepiece. The distalwindow 54, however, typically does not allow heating light to passtherethrough in order to absorb energy of the heating light to heat thedistal window 54. Heating of the distal window 54 prevents moisture fromcondensating on an exterior surface 56 of the distal window 54, therebypreventing fogging of the endoscope 12. The distal window 54 cancomprise an optical absorbing element or an optical absorbing element incombination with another optical element (e.g., a fully transparentwindow). This endoscope and its anti-fogging features are described indetail in U.S. Ser. No. 14/155,480, that published as U.S. Pub. Pat.App. No. 2014/0200406, and which is hereby incorporated by reference inits entirety.

The light source 14 depicted in FIG. 4 may generate light in five modes:(1) white light (a combination of red, green, and blue light), (2) alimited band imaging mode using the UV LED with a 415-nm filter and thegreen LED with a 540-nm filter, (3) a UV fluorescent mode using only theUV LED (and preferably no filter), which includes, but is not limitedto, a 5-ALA fluorescence mode, (4) a fluorescein mode using the UV LEDand the blue LED, preferably without filters, and (5) an endoscopedefogging mode in which all of the UV LED, the blue LED, the green LED,and the red LED are used.

In all five modes, the light is transmitted to and through an optic lensoutput system 22 (see FIG. 2) which focuses light onto a light pipe 24.The light pipe 24 preferably has a diameter substantially similar to thediameter of the fiber bundle of the endoscope and creates a homogeneouslight, which is then transmitted to the fiber optic light guide 26. Thelight guide 26 includes multiple optic fibers and is connected to alight post 28, which is part of the endoscope 12. As described above,the endoscope 12 has an illumination pathway and an optical channelpathway.

The endoscope 12 may include a notch filter 8, which allows at least 80%of infrared light in a wavelength range of 830 nm to 870 nm to passtherethrough and allows at least 80% of visible light in the wavelengthrange of 400 nm to 700 nm to pass therethrough, but blocks light havinga wavelength of 808 nm, and other similar wavelengths, if desired ormore practical. The notch filter 8 should have an optical density of OD5or higher. Alternatively, the notch filter 8 can be located in thecoupler 13.

The basic components of the light source 14 are shown in FIG. 4. Thelight source 14 includes an LED and filter section 129, which has afirst LED 130, a second LED 132, a third LED 134, and a fourth LED 136.Preferably, the first LED 130 emits light in the ultraviolet spectrum(preferably 400-440 nm and more preferably 405-420 nm) and includeslight having a wavelength range of 407-409 nm, the second LED 132 emitslight in the blue wavelength spectrum, the third LED 134 emits light inthe green wavelength spectrum, and the fourth LED 136 emits light in thered wavelength spectrum. The first LED 130 is activated by a first LEDdriver 138, the second LED 132 is activated by a second LED driver 140,the third LED 134 is activated by a third LED driver 142, and the fourthLED 136 is activated by a fourth LED driver 144. The drivers 138, 140,142, 144 are each powered by an external power supply 148.

The electrical currents supplied to the LEDs 130, 132, 134, 136, areadjusted using a Digital-to-Analog Converter (DAC) 130 a for the UV LED130, a DAC 132 a for the blue LED 132, a DAC 134 a for the green LED134, and a DAC 136 a for the red LED 136.

Adjacent the first LED 130 is a first optical component 130′, adjacentthe second LED 132 is a second optical component 132′, adjacent thethird LED 134 is a third optical component 134′, and adjacent the fourthLED 136 is a fourth optical component 136′. The optical components 130′,132′, 134′, 136′ are for the purpose of decreasing the angles of thepaths of the light emitted from the LEDs 130, 132, 134, 136,respectively. The optical components 130′, 132′, 134′, 136′ may be anycomponent that is capable of achieving the desired purpose, butpreferably are lenses or light pipes.

Adjacent the first optical component 130′ is a first motorized movablefilter 141, and adjacent the third optical component 134′ is a secondmotorized movable filter 145. The movable filters 141, 145 may be usedto filter light from the first and third LEDs 130, 134, respectively, ornot used depending on the desired imaging mode, as discussed below.

The first motorized movable filter 141 includes an optical filter 141′and a motor 141″ (see FIGS. 5-9). Activation of the motor 141″ allowsthe optical filter 141′ to be moved into or out of the pathway alongwhich light emitted by the first LED 130 travels. The second motorizedmovable filter 145 includes an optical filter 145′ and a motor 145″.Activation of the motor 145″ allows the optical filter 145′ to be movedinto or out of the pathway along which light emitted by the third LED134 travels.

Adjacent the first movable filter 141 is a first dichroic filter 150,adjacent the second optical component 132′ is a second dichroic filter152, and adjacent both the second movable filter 145 and the fourthoptical component 136′ is a third dichroic filter 154. The dichroicfilters 150, 152, 154 are each designed to reflect certain light andallow passage of other light therethrough, as described in more detailbelow.

A color sensor 160 is positioned adjacent the second dichroic filter152, at a location opposite the second LED 132. The color sensor 160detects light in the visible light wavelength spectrum, and when visiblelight is detected, it provides a signal to a color balance circuit/logicdevice 162. The amount of visible light detected is used by the colorbalance circuit/logic device 162 to provide signals to the LED drivers140, 142, 144 to adjust the intensity of one or more of the LEDs 132,134, 136, such that the preferred balance of light in the visiblespectrum is achieved. A switching logic device 164 is provided whichswitches the light source 14 among the various modes of the light source14.

FIGS. 5-9 show a more detailed view of the LED and filter section 129 ofthe first embodiment. In this arrangement, the first dichroic filter 150allows all visible light (i.e. light in the blue, green, and redwavelength spectra) to pass, while reflecting ultraviolet light. Thesecond dichroic filter 152 allows light in the red and green wavelengthspectra to pass while reflecting light in the blue wavelength spectrum.The third dichroic filter 154 allows light in the red wavelengthspectrum to pass, while reflecting light in the green wavelengthspectrum. A first optical lens 166 is located between the first dichroicfilter 150 and the second dichroic filter 152, and is for focusing lightreceived from the second dichroic filter 152 to be passed to the firstdichroic filter 150. A second optical lens 168 is located between thesecond dichroic filter 152 and the third dichroic filter 154, and is forfocusing light received from the third dichroic filter 154 to be passedto the second dichroic filter 152.

In operation in the first mode, shown in FIG. 5, power is not suppliedto the first LED driver 138, but is supplied to the second LED driver140, the third LED driver 142, and the fourth LED driver 144. Thus, inthis mode, no light is provided by the first LED 130, but light isprovided by the second LED 132, the third LED 134, and the fourth LED136. Also, the movable filters 141′, 145′ are positioned outside of thelight paths. Light in the red wavelength spectrum is emitted from thefourth LED 136 in the direction of the pathway 170 toward the fourthoptical component 136′ and the third dichroic filter 154, as shown inFIG. 5. Light in the green wavelength spectrum is emitted from the thirdLED 134 in the direction of the pathway 172 toward the third opticalcomponent 134′ and the third dichroic filter 154. Because the thirddichroic filter 154 allows red light to pass and reflects green light,the light along the pathway 174 is a mixture of light in the red andgreen wavelength spectra. This mixture of light from the pathway 174 isfocused by the second optical lens 168 and transmitted along the pathway176 to the second dichroic filter 152. Light in the blue wavelengthspectrum is emitted by the second LED 132 along the pathway 178 towardthe second optical component 132′ and the second dichroic filter 152.Because the second dichroic filter 152 allows red and green light topass and reflects blue light, the light along the pathway 180 is amixture of blue, green, and red light. This light is transmitted alongthe pathway 180 and through optical lens 166, which focuses the light.The focused blue, green, and red light mixture is transmitted along thepathway 182 toward the first dichroic filter 150, which allows bluelight, green light, and red light to pass. Thus, all of the lighttransmitted along the pathway 182 passes through the first dichroicfilter 150 to an exit pathway 184. The mixture of blue light, greenlight, and red light, i.e. white light, is transmitted along the exitpathway 184 to the lens system 22, as shown in FIG. 2.

In the second mode, shown in FIG. 6, power is provided to the first LEDdriver 138 and to the third LED driver 142, but is not provided to thesecond LED driver 140 or the fourth LED driver 144. Thus, the lightsource 14 provides ultraviolet light and light in the green wavelengthspectrum. Because the second LED 132 and the fourth LED 136 provide nolight in this mode, there is no light transmitted along the pathways 178and 170 (see FIG. 5). In this mode, the movable filters 141′, 145′ arepositioned in the pathways 186, 172, respectively, for filtering of thelight emissions of the first LED 130 and the third LED 134. The thirdLED 134 emits light in the green wavelength spectrum along pathway 172in the direction of the third optical component 134′, the movable filter145′, and the third dichroic filter 154, which reflects the green light.The movable filter 145′ filters the light from the LED 134 such thatlight reaching the dichroic filter 154 along pathway 172 is only visiblelight having a wavelength of approximately 540 nm. As a result, the540-nm light is transmitted along the pathway 174, to and through theoptical lens 168, along the pathway 176 to the second dichroic filter152, along the pathway 180 to and through the lens 166, and alongpathway 182 to the dichroic filter 150. The first LED 130 emitsultraviolet light along the pathway 186 in the direction of the firstoptical component 130′, the movable filter 141′, and the first dichroicfilter 150. The light reaching the movable filter 141′ is filtered suchthat light reaching the dichroic filter 150 along pathway 186 is onlyultraviolet light having a wavelength of approximately 415 nm. Becausethe first dichroic filter 150 passes light in the visible wavelengthspectrum, and reflects ultraviolet light, the result of lighttransmitted along the exit pathway 184 is a mixture of 540-nm visiblelight, and 415-nm ultraviolet light, as shown in FIG. 6. This mixture oflight is transmitted to the lens system 22.

As shown in FIG. 7, operation in the third mode involves supplying powerto only the first LED 130. Power is not supplied to the second LED 132,the third LED 134, or the fourth LED 136. The movable filter 141′ ispositioned outside of the light pathway 186 such that light from thefirst LED 130 travels along pathway 186 to and through the opticalcomponent 130′, and to the dichroic filter 150. The UV light emitted bythe first LED 130 is reflected by the first dichroic filter 150, andthus the light from the first LED 130 moves along the exit pathway 184to the lens system 22.

In the fourth mode, shown in FIG. 8, power is supplied to the first LEDdriver 138 and the second LED driver 140, but is not supplied to thethird LED driver 142 and the fourth LED driver 144. Thus, in this mode,light is provided only by the first LED 130 and the second LED 132.Also, the movable filters 141′, 145′ are positioned outside of the lightpaths. Light in the blue wavelength spectrum is emitted by the secondLED 132 along the pathway 178 toward the second optical component 132′and the second dichroic filter 152. This light is reflected by thesecond dichroic filter 152 and transmitted along the pathway 180 andthrough optical lens 166, which focuses the light. The focused bluelight is transmitted along the pathway 182 toward the first dichroicfilter 150, which allows blue light to pass. Light in the UV wavelengthspectrum is emitted from the first LED 130 in the direction of pathway186 toward the first optical component 130′, and to the dichroic filter150. The UV light emitted by the first LED 130 is reflected by the firstdichroic filter 150. The mixture of UV and blue light is transmittedalong the exit pathway 184 to the lens system 22, as shown in FIG. 2.

In the fifth mode, shown in FIG. 9, power is supplied to the first LEDdriver 138, the second LED driver 140, the third LED driver 142, and thefourth LED driver 144. Thus, in this mode, light is provided by thefirst LED 130, the second LED 132, the third LED 134, and the fourth LED136. Also, the movable filters 141′, 145′ are positioned outside of thelight paths. Light in the red wavelength spectrum is emitted from thefourth LED 136 in the direction of the pathway 170 toward the fourthoptical component 136′ and the third dichroic filter 154, as shown inFIG. 9. Light in the green wavelength spectrum is emitted from the thirdLED 134 in the direction of the pathway 172 toward the third opticalcomponent 134′ and the third dichroic filter 154. Because the thirddichroic filter 154 allows red light to pass and reflects green light,the light along the pathway 174 is a mixture of light in the red andgreen wavelength spectra. This mixture of light from the pathway 174 isfocused by the second optical lens 168 and transmitted along the pathway176 to the second dichroic filter 152. Light in the blue wavelengthspectrum is emitted by the second LED 132 along the pathway 178 towardthe second optical component 132′ and the second dichroic filter 152.Because the second dichroic filter 152 allows red and green light topass and reflects blue light, the light along the pathway 180 is amixture of blue, green, and red light. This light is transmitted alongthe pathway 180 and through optical lens 166, which focuses the light.The focused blue, green, and red light mixture is transmitted along thepathway 182 toward the first dichroic filter 150, which allows bluelight, green light, and red light to pass. Light in the UV wavelengthspectrum is emitted from the first LED 130 in the direction of pathway186 toward the first optical component 130′, and to the dichroic filter150. The UV light emitted by the first LED 130 is reflected by the firstdichroic filter 150. The mixture of UV light, blue light, green light,and red light is transmitted along the exit pathway 184 to the lenssystem 22, as shown in FIG. 2.

After the light, in the first mode, the second mode, the third mode,fourth mode, or fifth mode passes through the lens system 22, it istransmitted through the light pipe 24, through the fiber optic lightguide 26, and to the endoscope 12 via the light post 28. The lighttransmits through the illumination pathway of the endoscope to theobject 1.

In the first mode, visible light is reflected off of the object 1, aportion of which is received by the endoscope 12, and which istransmitted to the camera head 16 via the optical channel pathway. Inthe second mode, 415-nm UV light, as well as 540-nm visible light, aretransmitted to the object 1. The light is reflected or absorbed by theobject 1, and a portion of the reflected light is received by theendoscope 12. In the third mode, UV light is transmitted to the object1, and excites the fluorescent markers 2 in the object. The excitationof the fluorescent markers 2 causes the markers 2 to emit their ownlight, which is approximately 633-nm red/pink light. This 633-nm light,along with some reflected light, is transmitted to the camera head 16via the optical channel pathway. A filter may be used in the endoscope12 to block excitation light so as to prevent excitation light fromwashing out the fluorescent emission. In the fourth mode, 415-nm UVlight, as well as blue visible light, are transmitted to the object 1.The light in the 465 nm to 490 nm range excites fluorescein markers inthe object 1. The excitation of the fluorescent markers causes themarkers 2 to emit their own light in the 520 nm to 530 nm range. Afilter may be used in the endoscope 12 or in the coupler 13 to preventreflected blue light from washing out the received light emission. Inthe fifth mode, UV light, blue light, green light, and red light are alltransmitted to and through the endoscope 12. The light emitted can beused to defog the endoscope by reducing or eliminating moisture on theexterior surface 56 of the distal window via absorption of radiationfrom the light.

The light, in the first mode, the second mode, the third mode, or thefourth mode, returns along a path to the camera head 16 as shown anddescribed in WO 2014/152757 which is herby incorporated by reference inits entirety. The camera head 16 may include a trichroic prism or otherfilters.

The reference numeral 229 (FIG. 10) generally designates anotherembodiment of the present invention, being a second embodiment of an LEDand filter section of a light source. Since the LED and filter section229 is similar to the previously-described LED and filter section 129,similar parts and light pathways appearing in FIGS. 1-9 are representedby the same corresponding reference number, except for adding 100 to theprevious part numeral of those in FIGS. 1-9.

The LED and filter section 229 includes not only the four LEDs describedabove for the LED and filter section 129, but also includes an infraredlaser diode 243. In front of the laser diode 243 is an optical component243′. Infrared light emitted from the laser diode 243 travels alonglight pathway 288 through the optical component 243′ and to a dichroicfilter 250 which reflects infrared light, and passes blue, green, andred light emitted from LEDs 232, 234, and 236. The infrared and/or blue,green, and red light from the dichroic filter 250 travels along lightpathway 284 to and through a lens 269, and then along light pathway 290to another dichroic filter 251. The dichroic filter 251 passes infraredlight, as well as blue, green, and red visible light, while reflectinglight in the ultraviolet spectrum. Thus, light emitted from the LED 230in the ultraviolet spectrum travels along light pathway 286, through anoptical component 230′ (and optionally a movable filter 241′) and isreflected by the dichroic filter 251. Any light from the LEDs 230, 232,234, 236 and/or light from the laser diode 243 then travels along anexit light pathway 292 to the light output and to and through theoptical lens output system 22. The LED and filter portion 229 includestwo movable filters 241, 245, which may be moved into or out of thelight paths 286, 272, respectively, in similar fashion to that describedabove with respect to the LED and filter section 129. The laser diode243 is preferably an infrared diode (denoted by the letters IR) whichemits light having a wavelength in the range of about 805 nm to about810 nm, and more preferably having a wavelength of about 808 nm.

Accordingly, the LED and filter section 229 may function in at least sixmodes, those being the five modes discussed above, as well as aninfrared mode for light emission in a wavelength range of about 805 nmto about 810 nm. This mode is especially useful for using ICG markerswhich reflect a fluorescence. An additional mode may use the IR lightfor defogging as described in U.S. Pat. Pub. No. 2014/0200406.

An infrared sensor may be positioned adjacent the first dichroic filter250, at a location opposite the laser diode 243. The infrared sensordetects the presence of infrared light, and when the presence ofinfrared light is detected, it provides a signal to a laser diodeintensity control circuit. The laser diode intensity control circuit isconnected to the laser diode driver and controls the intensity of thelight emitted from the laser diode 243.

The reference numeral 329 (FIG. 11) generally designates anotherembodiment of the present invention, being a third embodiment of an LEDand filter section of a light source. Since the LED and filter section329 is similar to the previously-described LED and filter section 229,similar parts and light pathways appearing in FIG. 10 are represented bythe same corresponding reference number, except for adding 100 to theprevious part numeral of those in FIG. 10.

The LED and filter section 329 includes a blue LED 332, a green LED 334,a red LED 336, and optionally a UV LED 330. The LED and filter section329 also includes an infrared laser configuration 343. Due to spaceconstraints in some light source systems, and the desire to have a heatsink available for each LED/laser, the laser configuration 343 includestwo infrared laser diodes as shown in FIGS. 12-13.

FIG. 12 depicts the infrared laser configuration 343, that includes afirst infrared laser diode 400, which preferably emits an 808-nminfrared laser, and a second infrared laser diode 402, which preferablyemits a 780-nm infrared laser. Each of the laser diodes 400, 402 areconnected to a heat sink 404. The heat sink 404 is capable of absorbingthe heat from each of the laser diodes 400, 402, especially since thelaser diodes 400, 402 are typically used separately from one another.

As shown in FIG. 13A, the laser configuration 343 may include more thantwo laser diodes. The laser configuration 343 depicted in FIG. 13B hasfour laser diodes 400, 401, 402, 403, while only using one light sourceslot/heat sink.

In FIGS. 12, 13A, and 13B the laser diodes 400, 401, 402, 403 are shownto be one above the other vertically, however other configurations arecontemplated. Preferably though, an optical prism 406 is placedbetween/among the laser diodes 400, 402 and is capable of receiving anemission from each of the laser diodes, such as laser diodes 400, 402,as shown in FIG. 13B. A laser emission is received by the optical prism406 from the laser diode 400 via light path 408 and receives a laseremission from laser diode 402 via light path 410. The optical prism 406is capable of redirecting the emissions from laser diodes 400, 402 alonglight path 388 toward and through an optical component 343′ and to adichroic filter 350. The emissions from the laser diodes 400, 402 aredirected out of the optical prism 406 along concentric optical pathways388 a and 388 b, respectively.

Another embodiment is depicted in FIG. 14. This embodiment is one thattypically would have a small size where space limitations are at apremium. The light source 500 includes four different light emissioncomponents. Those light source components are a white light LED 502, aUV LED 504, an infrared 808 nm laser diode 506, and an infrared 780 nmlaser diode 508. The infrared 808 nm laser diode 506 and the infrared780 nm laser diode 508 preferably both use the same “slot” and thus thesame heat sink as depicted in FIGS. 12-13.

The white light LED 502 is preferably a powerful LED and can be usedduring normal endoscopic illumination. The white light emitted from theLED 502 could be filtered and separated into individual color componentsand used for other imaging modalities. The light emitted from the LED502 travels along a light path 510 to and through an optical component512 and to a dichroic filter 514 which allows visible light to passtherethrough.

The LED 504 emits ultraviolet light along a light pathway 516 to andthrough an optical component 518 and to the dichroic filter 514. Thedichroic filter 514 reflects the ultraviolet light from the LED 504 andthus both visible light and ultraviolet light move along light path 520to a second dichroic filter 522 which allows both visible light andultraviolet light to pass therethrough.

Infrared light from either laser diode 506 or laser diode 508 is emittedfrom the slot 509 along a light path 524 to and through an opticalcomponent 526 and to the second dichroic filter 522. The second dichroicfilter 522 reflects infrared light. Light reflected by or passingthrough the dichroic filter 522 moves along a light path 528.

The light along light path 528 is directed to a filter mechanism 530,such as a filter wheel, which can change optical filters, depending onthe mode desired. It is contemplated that other types of filters couldalso be used with the light engine 500.

The light engine 500 is capable of multiple imaging modalities, whilehaving a smaller overall footprint size than a typical light enginebecause it requires fewer heat sinks and slots. The light engine 500 iscapable of at least the following imaging modalities: white light, ICG,on target drug (780 nm), UV fluorescent, limited band imaging,fluorescein, and a backlight for laser modes.

FIGS. 15-17 depict a first embodiment of a modular light engine systemfor a light source 614. The light source 614 has a port or opening 614 awhich is shaped and sized to receive a modular light engine 614 b. Thelight source 614 therefore may use interchangeable light engines, suchas light engine 614 b, which is essentially an LED and filter sectionsimilar to that of the LED and filter sections 129, 229, 329, 500discussed above. Accordingly, the user may select a particular modularlight engine for the particular surgical procedure to be performed.Therefore, the modular light engine 614 b may include a variety ofdifferent filters and lights. An example of such a modular light engineis shown in FIG. 17, which has components similar to the secondembodiment of the LED and filter section 229, discussed above.Specifically, the modular light engine 614 b depicted in FIG. 17 includeLEDs 630, 632, 634, and 636, with corresponding optical components 630′,632′, 634′, and 636′. In addition, included is a infrared laser diode643 with corresponding optical component 643′. Four dichroic filters650, 651, 652, and 654 are included for proper reflection and/or passingof light for a particular mode, and lenses 666, 668, 669 are includedfor focusing of light.

Another embodiment of a light source 714 with a modular light engine 714b is depicted in FIGS. 18-20. The light source 714 includes an openingor port 714 a which is shaped and sized to receive the modular lightengine 714 b.

The modular light engine 714 b is different from that of 614 b in thatthe modular light engine 714 b does not include LED lights, but useslight from LEDs or other light sources in the light source 714 for lightin the visible spectrum and/or infrared spectrum.

As depicted in FIGS. 19-20, the modular light engine 714 b includes ahousing 1100, a light input 1102, and a light output 1104. Inside thehousing 1100 are a battery pack 1106, which may be of the rechargeabletype, a UV LED chip board 1108 which is capable of providing UV lightvia an LED, and a microcontroller 1110 for controlling the UV LED chipboard 1108. Also included within the housing 1100 are a color filterwheel 1112, a motor 1114 for turning the color filter wheel 1112 whendesired, and a variety of optical prism blocks 1116 for providing lightpaths for the various light inputted into and generated by the modularlight engine 714 b.

FIG. 20 shows the various light paths for the light which may be emittedby the modular light engine 714 b. Specifically, as shown, red, blue,and green light may be inputted via light input 1102 and follow alongthe light path 1117 as shown in FIG. 20, including through one or moreof the prism blocks 1116, and to and through a portion of the filterwheel 1112. In addition, the light path 1118 for UV light generated bythe UV LED chip board 1108 is depicted in FIG. 20. As shown, the UVlight travels from the chip board 1108, to and through a portion of thefilter wheel 1112, and to and through one or more of the prism blocks1116 before exiting via the light output 1104.

FIGS. 21-22 depict a light engine port 1200 which may be part of a lightengine such as light source 614 and is configured to receive and connectto a light module such as light module 614 b. The port 1200 includes afloor 1202 which has two slots 1204, 1206 therein for easy centering andalignment of a light module. The port 1200 also includes a substantiallyvertically oriented receiving member 1208 which has a groove 1210therein that is sized to receive a portion of a front panel of a lightmodule.

The port 1200 also includes multiple heat sinks 1212, 1214, 1216, 1218,1220 which are sized and positioned to contact a thermal interface of anLED chip board on a light module. The heat sinks 1212, 1214, 1216, 1218,1220 allow thermal management of the light source, including a lightmodule via forced air cooling, while allowing the light module to beremovable.

The port 1200 also preferably includes multiple high current powersupply connectors, such as banana plugs 1222, for connection to a lightmodule. In addition, an electrical pinout block 1224 is included toprovide power and electronic communication to any sensors, motors, orother components that are part of the light module.

The groove 1210 in the receiving member 1208 is generally semicircularin shape with a circular indentation and is therefore shaped and sizedto receive a circular portion of the end plate of a light module.

The reference numeral 1300 (FIGS. 23-24) generally designates anotherembodiment of a light module of the present invention. Since lightmodule 1300 is similar to previously described light module 614 b,similar parts appearing in FIGS. 17 and 23-24, respectively, arerepresented by the same, corresponding number, except for the additionof 700 in the numerals of the latter. The light module 1300 includes afront panel 1370 which has a light port therein defined by a round outerlip 1372. The outer lip 1372 is sized and shaped to fit within and bereceived by the groove 1210 in the receiving member 1208. The LEDs andlaser diode 1330, 1332, 1334, 1336, and 1343 each have preferably twopower receiving ports 1374 configured to receive and engage with bananaplug connectors such as the banana plug connectors 1222 of the port1200. In addition, each of the LEDs and the laser diode has a thermalinterface for conveying heat to a heat sink for that particular LED orlaser diode. The LED 1330 has a thermal interface 1376 which is sizedand configured to engage with the heat sink 1212 of the base 1200, theLED 1343 includes a thermal interface 1378 which is sized and configuredto engage with the heat sink 1214, the LED 1332 has a thermal interface1380 which is sized and configured to engage with the heat sink 1216,the LED 1334 has a thermal interface 1382 which is sized and configuredto engage with the heat sink 1218, and the LED 1336 has a thermalinterface 1384 which is sized and configured to engage with the heatsink 1220. The thermal interface 1384 is at an angle “A” with respect tothe longitudinal axis of the LED 1336, as shown in FIG. 23. Angling ofthe thermal interface 1384, as well as the face of its respective heatsink 1220 creates an increased compression between the two to maintainheat transfer away from the LED light source. Angle A is preferablybetween about 20° and about 30°, and more preferably is about 25°. Awedge 1386 is placed between the thermal interface 1384 and the LED 1336and is preferably of a material that is a good heat conductor, such ascopper.

The light module 1300 also includes a pinout block (female) receiver1388 for receiving electrical power from the port 1200, which may beused for a variety of purposes, including movement of one or morefilters during the operation of the light source.

As depicted in FIG. 24, the light module 1300 preferably has a base 1387with two feet 1388, 1390 depending therefrom. The feet 1388, 1390 arespaced apart from each other and are sized and shaped to fit withingrooves 1204 and 1206, respectively.

FIG. 25 depicts the beginning of engagement between the light module1300 and the port 1200. The straight arrows in FIG. 25 show thedirection of movement of the light module 1300, once feet 1388, 1390 arealigned with and guided into the grooves 1204, 1206, respectively, forthe light module 1300 to be fully connected and engaged with the port1200.

The light source, including the port 1200, the light module 1300, orpreferably a combination of the two, may include a motorizedmagnetically driven optical filter, which is shown in FIGS. 24 and 26.The magnetically driven optical filter device 1400 includes a movabledriven filter 1402 which includes a filter arm 1404. The filter arm 1404is attached at its distal end to a front panel 1406 and a magnet 1408.

The front panel 1406 includes a frame 1410 and an inner member 1412attached to the frame 1410. The inner member 1412 has an aperture 1414therein which may or may not include a lens.

On the side of the front panel 1406 opposite the filter 1402 is a motor1416. The motor 1416 may receive electrical power from the pin 1224 ofthe base 1200 via the pin receiving 1388. The motor 1416 drives a leverarm 1418 which is attached to a magnet 1420.

In operation, the motor 1416 may be used to move the lever arm 1418 in acounterclockwise or clockwise direction, thereby moving the magnet 1420with it. Due to magnetic forces, the magnet 1408 is moved along withmagnet 1420, which in turn moves the filter arm 1404 and the filter 1402in a clockwise or counterclockwise direction to move the filter 1402into or out of the light path of the light exiting the light module1300.

The above-described light sources and light source engines provide aflexible system by which various modes of light output can be achievedfor a variety of different medical procedures. The modularity of themodular light engines gives the potential of using a variety ofdifferent modular pieces without having to purchase a whole new lightsource system, while providing increased capability as well as thepotential for future modular components which may be used with existinglight sources.

Although particular preferred embodiments of the invention have beendisclosed in detail for illustrative purposes, it will be recognizedthat variations or modifications of the disclosed apparatus, includingthe rearrangement of parts, lie within the scope of the presentinvention.

1. A medical light source comprising: a first light comprising an LEDcapable of emitting light in a visible wavelength spectrum; a secondlight comprising a first light emitter capable of emitting light in afirst infrared spectrum and a second light emitter capable of emittinglight in a second infrared spectrum, the second light comprising atleast one optical element for redirecting light emitted from both thefirst light emitter and the second light emitter.
 2. The medical lightsource of claim 1, further comprising at least one heat sink, the atleast one heat sink engaging the second light and configured to removeheat from both the first light emitter and the second light emitter. 3.The medical light source of claim 1, wherein the at least one opticalelement comprises a prism.
 4. The medical light source of claim 1,wherein the at least one optical element redirects the light emittedfrom both the first and second light emitters toward an opticalcomponent.
 5. The medical light source of claim 1, further comprising atleast one dichroic filter for combining light from the first light andlight from the second light.
 6. The medical light source of claim 1,wherein the first light emitter emits light in a first direction and thesecond light emitter emits light in a second direction that is oppositethe first direction.
 7. The medical light source of claim 1, wherein thesecond light comprises more than two light emitters.
 8. The medicallight source of claim 7, wherein the more than two light emitters arearranged in a stack.
 9. The medical light source of claim 1, wherein thefirst infrared spectrum comprises 808 nm light.
 10. The medical lightsource of claim 9, wherein the second infrared spectrum comprises 780 nmlight.
 11. The medical light source of claim 1, further comprising athird light comprising an LED capable of emitting light in anultraviolet wavelength spectrum.
 12. The medical light source of claim1, wherein the first and second light emitters comprise laser diodes.13. A method for generating light from a medical light source, themethod comprising: emitting light in a visible wavelength spectrum froma first light of the medical light source; emitting light in a firstinfrared spectrum from a first light emitter of a second light;redirecting light emitted from the first light emitter by at least oneoptical element of the second light; emitting light in a second infraredspectrum from a second light emitter of the second light; andredirecting the light emitted from the second light emitter by the atleast one optical element of the second light.
 14. The method of claim13, wherein the light in the first infrared spectrum is emitted at aseparate time than the light in the second infrared spectrum.
 15. Themethod of claim 13, further comprising removing heat from both the firstlight emitter and the second light emitter by at least one heat sinkthat engages the second light.
 16. The method of claim 13, wherein theat least one optical element comprises a prism.
 17. The method of claim13, further comprising redirecting the light emitted from the first andsecond light emitters toward an optical component.
 18. The method ofclaim 13, further comprising combining light from the first light andlight from the second light via at least one dichroic filter of themedical light source.
 19. The method of claim 13, wherein the firstlight emitter emits light in a first direction and the second lightemitter emits light in a second direction that is opposite the firstdirection.
 20. The method of claim 13, wherein the second lightcomprises more than two light emitters.
 21. The method of claim 20,wherein the more than two light emitters are arranged in a stack. 22.The method of claim 13, wherein the first infrared spectrum comprises808 nm light.
 23. The method of claim 22, wherein the second infraredspectrum comprises 780 nm light.
 24. The method of claim 13, furthercomprising emitting light in an ultraviolet wavelength spectrum from athird light of the medical light source.
 25. The method of claim 13,wherein the first and second light emitters comprise laser diodes.